Keithley 580 Micro-ohmmeter

The Keithley 580 Micro-ohmmeter is a precision instrument for accurate low-resistance measurements from 200 mΩ to 200 kΩ across seven selectable ranges. It employs four-terminal Kelvin sensing to eliminate lead resistance errors, delivering 10 µΩ resolution on the lowest range and accuracy to ±0.05% of reading + 0.1 µΩ. The microprocessor-based design supports selectable pulsed or DC test current from 10 mA to 10 A, with polarity selection and automatic thermal offset cancellation in pulsed mode.

A dry circuit test function limits test voltage to 20 mV on sensitive contact junctions. Auto or manual ranging completes in 200 ms per range change, with settling time under 1 second and 3 readings per second conversion rate. The instrument displays results on a 4½ digit ±20,000 count LCD and tolerates 30V rms common mode voltage.

Optional interfaces include the Model 5802 for isolated analog output and IEEE-488 control, or the Model 1755 for digital calibration via GPIB.

Technical Specifications

• Measurement Ranges: 200 mΩ to 200 kΩ (seven ranges)


• Resolution: 10 µΩ minimum


• Accuracy: ±0.05% of reading + 0.1 µΩ


• Test Current: 10 mA to 10 A at ±0.2% of reading + 0.02 mA


• Test Voltage: 20 mV (dry circuit); 1 V (standard)


• Settling Time: <1 second to within 10 counts


• Conversion Rate: 3 readings/second typical


• Ranging: Auto (200 ms) or manual


• Display: 4½ digit LCD, ±20,000 counts


• Maximum Input Overload: 10 V limited to 10 A


• Common Mode Voltage: 30 V rms at DC, 50–60 Hz


• Temperature Coefficient: ±(0.1 × accuracy)/°C from 0–18 °C and 28–50 °C


• Power Supply: 105–125 V or 210–250 V, 50–60 Hz, 12 VA


• Dimensions: 89 mm H × 241 mm W × 300 mm D


• Weight: 3.2 kg

Key Features

• Four-terminal Kelvin sensing eliminates lead resistance errors


• Selectable pulsed or DC source current with automatic thermal offset cancellation


• Dry circuit test protects sensitive contact junctions at ≤20 mV


• Positive or negative polarity selection


• Optional battery pack (Model 1978) for ~6 hours operation

Typical Applications

• Component evaluation and material resistance characterization


• Quality control testing of low-resistance connections


• Contact resistance assessment in sensitive circuits

Compatibility & Integration

• Model 5802: Isolated analog output (1 V = 10,000 counts at ×1 gain) and IEEE-488 interface; ±(0.25% of reading + 2 mV) analog accuracy; 1000 Ω output impedance; maximum ±4 V output


• Model 1755: Digital calibration interface via IEEE-488 controller


• Rear panel banana jack connectors for measurement and external trigger inputs